Device and Method for Sucking in, Temporarily Storing, and Leading Away a Thread, and Textile Machine

ABSTRACT

A device (1) for drawing in and intermediately storing a thread (2), comprising a suction chamber (3), wherein the suction chamber (3) includes an entry opening (8) and an exit opening (9), which define a direction of flow, wherein negative pressure can be applied to the exit opening (9) in order to generate an air flow (4). Moreover, the device comprises a depositing surface (5) arranged in the suction chamber (3), on which the thread (2) can be intermediately stored, and a flow element (6) arranged in the suction chamber (3), with the aid of which the air flow (4) can be directed through the suction chamber (3). The suction chamber (3) is divided into a first region (14) and a second region (15) with the aid of the depositing surface (5) and the flow element (6) is displaceable between a first position, in which the air flow (4) is guided through the depositing surface (5) and through the second region (15), and a second position, in which the air flow (4) is guided past the depositing surface (5) through the first region (14). A textile machine comprising a plurality of workstations arranged next to one another in the longitudinal direction of the textile machine is characterized in that the workstations each comprise such a device. In a corresponding method for drawing in and intermediately storing a thread (2), the thread (2) is sucked into the suction chamber (3) with the aid of an air flow (4) and is intermediately stored on a depositing surface (5) arranged in the suction chamber (3). The air flow (4) is directed through the suction chamber (3) with the aid of the flow element (6). The suction chamber (3) is subdivided into a first region (14) and a second region (15) with the aid of the depositing surface (5) and the flow element (6) is displaced between the described positions.

The present invention relates to a device for drawing in and intermediately storing a thread, comprising a suction chamber, wherein the suction chamber includes an entry opening and an exit opening, which define a direction of flow of the device, wherein a negative pressure can be applied to the exit opening in order to generate an air flow through the suction chamber, comprising a depositing surface, which is arranged in the suction chamber, is air-permeable, and is impermeable to the thread, on which the thread can be intermediately stored, and comprising a flow element arranged in the suction chamber, with the aid of which the air flow can be guided through the suction chamber. Moreover, the invention relates to a textile machine comprising such a device and to a corresponding method.

DE 39 08 463 A1 describes a device for the intermediate storage of a double thread formed from two thread components. The device is arranged between a thread-delivery unit and a thread-connecting device on a textile machine, in order to be able to temporarily pick up the thread—which is further delivered by the thread-delivery unit after a thread break—during the connection of the thread ends. The device comprises a suction chamber, in which a depositing surface is arranged, on which the thread can be stored for the interim. The device is complex to operate, however, since a discharge of the thread out of the suction chamber takes place via an additional auxiliary suction chamber. In addition, the device is not suitable for drawing in and unwinding a thread from a package, for example, on a spinning machine or winder.

The problem addressed by the present invention is therefore that of creating a device, which is easy to operate. Moreover, a corresponding textile machine and a corresponding method are to be provided.

The problem is solved using a device and a method having the features of the independent claims.

The invention relates to a device for drawing in and intermediately storing a thread, comprising a suction chamber, wherein the suction chamber includes an entry opening and an exit opening, which define a direction of flow of the device, and wherein a negative pressure can be applied to the exit opening in order to generate an air flow through the suction chamber, comprising a depositing surface, which is arranged in the suction chamber, is air-permeable, and is impermeable to the thread, on which the thread can be intermediately stored, and comprising a flow element arranged in the suction chamber, with the aid of which the air flow can be guided through the suction chamber.

A thread end traveling on the package can be sought on the package, for example, in the event of a thread break, with the aid of the air flow and with the aid of a suction nozzle, which is additionally provided, if necessary. For this purpose, the package can be operated counter to a winding direction and can be acted upon by the air flow, which flows away from the bobbin through the suction chamber. In this process, the thread end lifts up off the package and is sucked into the suction chamber by the air flow. As a result, the thread is fixed in a defined position by the suction draught of the suction chamber, from which it can be picked up by different handling units of a piecing device and pieced. Before the piecing process, a portion of the thread unwound from the package is cut off, in order to remove any thread defects and to create a defined thread end for the piecing. An additional thread length necessary for the piecing, for example, in order to form a thread loop, is provided in a way known per se by unwinding the thread from the package. This portion of the thread to be trimmed off can be picked up, during the drawing-in, by the device and stored for the interim, until it is subsequently cut off and discarded. The depositing surface can be designed, for example, as a screen. During the interim storage of the thread on the depositing surface, a thread ball forms, which initially remains on the depositing surface even after the thread has been trimmed. The air flow and, therefore, also the thread and the accumulated thread ball are guided through the suction chamber with the aid of the flow element. The accumulation of the thread into the formation of thread ball has the advantage that the thread ball can be discharged in its entirety and, as a result, the thread can be better recycled. In addition, due to the formation of a thread ball, the situation can be prevented, in which long, discharged thread pieces get tangled in a negative pressure duct of the textile machine during their disposal and must then be removed by the operating personnel, which is time-consuming.

Alternatively, the intermediately stored thread, at least a portion of the intermediately stored thread, can also be withdrawn from the device again in order to be pieced, with the thread ball being opened, in order to provide a thread length necessary for the piecing. It is necessary to cut the thread in this variant as well, and so a portion of the intermediately stored thread remains in the device and is discharged out of the device. The air flow is guided through the suction chamber with the aid of the flow element in this case as well. The device is equally suited for the two above-described methods with respect to piecing.

It is provided that the suction chamber is divided into a first region and a second region with the aid of the depositing surface and that the flow element is displaceable between a first position, in which the air flow is guided through the depositing surface and through the second region, and a second position, in which the air flow is guided past the depositing surface through the first region. When the air flow is guided through the depositing surface in the first position of the flow element, the air flow is allowed to pass through but the thread is held back, and so the thread is deposited there. When the air flow is directed past the depositing surface in the second position of the flow element, however, the thread or the thread ball, which has accumulated on the depositing surface, can be detached from the depositing surface and discarded through the suction chamber with the aid of the air flow. Due to the subdivision of the suction chamber with the aid of the depositing surface, relatively simple interim storage and discharge with the aid of a single suction chamber is made possible. Due to the change of the position of the flow element, the thread-guiding air flow can be directed, in a simple way, either through the depositing surface or past the depositing surface in order to discard the thread through the suction chamber.

It is advantageous when the entry opening is designed as a common entry opening of the first and the second regions, wherein the thread can be sucked into the suction chamber through the common entry opening. Due to the common entry opening, the device is suitable for different intended uses on different textile machines, for example, as well, for picking up and unwinding a package-side thread end after an interruption of production on a spinning machine or winder.

In an advantageous refinement of the invention, the flow element is displaceable into a third position, in which the exit opening of the suction chamber is blocked. The air flow through the suction chamber is interrupted as a result. Due to the blockage of the air flow, energy can be saved during regular operation when there is no need to draw in and handle a thread.

Moreover, it is advantageous when the flow element comprises a swivelable flap and/or a displaceable slider and/or a rotatable turning valve. With the aid, for example, of the swivelable flap, the first position, the second position, and/or the third position can be implemented particularly easily via swiveling. In the first position, for example, the flow element can block the first region of the suction chamber in such a way that the air flow can flow only through the depositing surface into and through the second region. In the second position, however, the flow element can block the second region of the suction chamber in such a way that the path for the air flow through the depositing surface and the second region is blocked, while the path through the first region is released for the air flow. In a third position, the flow element can completely seal off the suction chamber, for example, in the region of the exit opening, so that the air flow is blocked.

It is also advantageous when the depositing surface is fixedly arranged in the suction chamber, i.e., in a stationary and immovable manner. Therefore, only the flow element can be displaced between the first position, the second position, and, if necessary, the third position, so that the structural and control-related complexity is low. In addition, in the case of a fixed depositing surface, the risk of thread pieces or residual thread, which is to be discarded, becoming stuck in the suction chamber is reduced. It is also conceivable, however, that the depositing surface is also displaceably arranged in the suction chamber. In this case, for example, the depositing surface can be adjusted in different ways for different machines, different thread types, or different flow conditions. The depositing surface, in addition to the flow element, can also be displaceable between at least two positions, in order, for example, to assist in the discharge of the intermediately stored thread by way of a tilting of the depositing surface. The depositing surface can be adjusted separately from the flow element or together with the flow element.

It is also advantageous when the depositing surface is oriented in the suction chamber essentially in a longitudinal direction, i.e., in the direction of flow. The depositing surface divides the suction chamber into the first region and the second region, which extend essentially in parallel to one another in this case. The depositing surface can also be arranged obliquely, i.e., at an angle with respect to the flow direction, which is defined by the entry and exit openings of the suction chamber. As a result, the discharge of the stored thread with the aid of the air flow, which has been changed after the repositioning of the flow element, can be facilitated.

It is also advantageous when the depositing surface is oriented in parallel to or at a shallow angle with respect to the direction of flow. As a result, a particularly orderly depositing of the thread can be achieved, in particular in loops lying next to one another in an offset manner, which facilitates the subsequent withdrawal of the thread from the device.

Moreover, it is advantageous when the flow element is arranged downstream from the depositing surface in the direction of flow. As a result, the depositing surface and the flow element cooperate directly with one another or the air flow can be directed, in an easy way, either through or past the depositing surface with the aid of the flow element. The structural complexity is kept low in this case.

In addition, it is advantageous when the flow element is displaceable with the direction of flow from the first position into the second position. When the thread is to be discarded, after the interim storage, via the exit opening, the movement of the flow element in the direction of material flow, i.e., the direction in which the thread is discharged, ensures that the thread cannot become stuck on the flow element.

Moreover, it is advantageous when a thread monitor is arranged upstream from the depositing surface in the direction of flow, in particular in the region of or in the entry opening. With the aid of the thread monitor, it is possible to detect whether a thread is present in the suction chamber, or not. As a result, it is possible to detect whether the thread seeking on the package was successful, or not, at an early point in time. The thread monitor can be connected to a control system, which initiates the displacement of the flow element between the first position, the second position, and, if necessary, the third position depending on the detection of a thread. The thread monitor is preferably designed as an optical sensor. The thread monitor can comprise, for example, a light barrier, with the aid of which it can be contactlessly detected whether the thread is arranged in the suction chamber. Additionally or alternatively, the thread monitor can also comprise a microwave sensor, which can also contactlessly detect the thread in the suction chamber.

With respect to the arrangement of the thread monitor in the suction chamber, it is also advantageous that the thread executes only a comparatively slight movement at this point, as compared to the arrangement in the region of the opening of a suction nozzle, and can therefore be more easily detected. It is also conceivable, however, to arrange the thread monitor not in the entry region of the suction chamber, but rather in the exit region of a suction nozzle connected to the suction chamber or in an intermediate piece, which connects the suction nozzle to the suction chamber.

It is also advantageous when the entry opening is connected, directly or via an intermediate piece, to a suction nozzle, in particular a suction nozzle for drawing in a thread from a package. As a result, the device is suitable not only for drawing in, but also for seeking a thread end on a package surface.

With respect to the suction chamber and/or the intermediate piece and/or the suction nozzle, it is advantageous when these/this are/is designed as injection-molded parts or as an injection-molded part, in particular as plastic injection-molded parts or as a plastic injection-molded part.

It is also advantageous when the thread monitor is arranged in a sensor housing made of plastic injection molding. The sensor housing can also be designed as one piece with the suction chamber or the intermediate piece or the exit region of the suction nozzle. If the thread monitor is arranged in such a sensor housing, the thread monitor is consistently correctly aligned with respect to the region to be monitored and is protected against impurities. In addition, as a result, the thread monitor can be integrated into the device or into the suction chamber in an easy way.

Moreover, the invention relates to a textile machine, in particular a spinning machine or a winder, comprising a plurality of workstations arranged next to one another in the longitudinal direction of the textile machine. The workstations each comprise a device of the type described above. The device is therefore advantageously designed as a workstation-specific device and can be utilized on a machine having standalone automation.

With respect to the textile machine, it is also advantageous when the exit openings of the suction chambers are each connected to a negative pressure duct extending in the longitudinal direction of the textile machine. As a result, the intermediately stored residual thread or thread balls can be discarded through the negative pressure duct of the machine in a usual way.

Moreover, the invention relates to a method for drawing in and intermediately storing a thread, in particular for drawing in a thread from a package. The method can be carried out with the aid of a device, which is designed according to one or more features of the preceding description and/or the following description. In the method, the thread is sucked into a suction chamber with the aid of an air flow flowing from an entry opening to an exit opening, wherein the thread is intermediately stored on a depositing surface arranged in the suction chamber, and in the case of which the air flow is directed through the suction chamber with the aid of a flow element arranged in the suction chamber.

According to the invention, the suction chamber is subdivided into a first region and a second region with the aid of the depositing surface, and the flow element is moved into a first position, in which the air flow is guided through the depositing surface and through the second region, in order to draw in and intermediately store the thread.

Moreover, it is advantageous when the entry of the thread into the suction chamber is monitored with the aid of a thread monitor. The thread monitor can then output an appropriate signal to a control system upon detection or, if necessary, upon non-detection of the thread, which initiates the displacement of the flow element between the first position, the second position, and, if necessary, the third position.

As described above with respect to the device, the thread can be intermediately stored in the form of a ball and subsequently sucked out of the device and discarded. Alternatively, it is also possible, however, to withdraw at least a portion of the intermediately stored thread from the device again, in order to provide a thread length necessary for the piecing.

It is therefore advantageous when the thread, while being drawn in, is deposited on the depositing surface in the shape of loops and in a laterally offset manner, wherein the depositing surface becomes successively obstructed. As a result, the thread is deposited on the depositing surface in an orderly manner, which facilitates the subsequent withdrawal of the thread from the suction chamber. Such a withdrawal of the thread from the suction chamber through the entry opening can be necessary, for example, during the piecing of the thread, in order to provide a necessary additional length of the thread for forming a thread loop. During the loop-shaped and laterally offset depositing of the thread, use is made of the effect that the thread increasingly seals off the cross-section of the depositing surface, so that newly incoming partial lengths of the thread are preferably deposited in the area where the cross-section is still exposed. Due to the turning of the yarn, the thread is deposited in such a way that loops form.

It is particularly advantageous when a predetermined length of the thread is sucked into the suction chamber. This can be utilized, for example, in order to remove a faulty yarn piece out of the thread or also to provide a necessary, defined length of the intermediately stored thread out of the suction chamber during the piecing process. The sucking-in of the defined length of the thread can take place, for example, in that the thread monitor is arranged in the suction chamber or the exit region of the suction nozzle or also the intermediate piece at a distance, which corresponds to the desired, predetermined length. As soon as the thread is registered by the thread monitor, the predetermined is sucked into the suction nozzle and/or the suction chamber and the further drawing-in of the thread from the package can be stopped. For this purpose, the thread monitor can be connected to a control unit of the workstation of the textile machine, which, in turn, stops the reverse rotation of the package and, therefore, the further delivery of the thread into the suction nozzle and/or the suction chamber. The sucking-in of the predetermined length of the thread can also take place, however, with the aid of a certain specified operating time during the reverse rotation of the package or a certain number of revolutions of the package with consideration for the instantaneous package diameter.

In order to provide a defined length of the intermediately stored thread out of the suction chamber during piecing, it is therefore also advantageous when the intermediately stored thread is partially withdrawn again through the entry opening. As a result, it is possible, for example, to form a thread loop during piecing, which is presented to the piecing units of the workstation. The flow element preferably remains in the first position in this case, in order to ensure the orderly withdrawal of the thread with the aid of the suction draught, which continues to act on the thread. Due to this retention force on the thread, the formation of laps and twists in the thread can be avoided.

It is therefore also advantageous when a thread loop is formed from the thread withdrawn through the entry opening, wherein the flow element preferably also remains in the first position, in order to ensure a constant thread tension during the formation of the thread loop. The risk of swirling and lap formation is further reduced as a result. It can also be achieved, as a result, that, in the case of a textile machine, the same retention forces and, therefore, the same conditions prevail at all workstations.

In order to discharge the thread, the flow element is preferably moved into a second position, in which the air flow is guided past the depositing surface through the first region. As a result, the thread condensed into a thread ball on the depositing surface can be discarded, wherein, due to the thread ball, the risk of thread getting stuck in the suction chamber is reduced. The risk of thread getting stuck is further reduced due to the fact that the flow element is always displaced together with the air flow, which carries the intermediately stored thread along. A further advantage is that the thread can be better recycled in the form of a thread ball.

It is advantageous when the thread is cut after it has been drawn into the suction chamber or after it has been partially withdrawn through the entry opening, the cutting preferably taking place outside the suction chamber, and the entry of the newly created thread end into the suction chamber is monitored with the aid of the thread monitor. After the newly created thread end has entered the suction chamber, which can be detected, for example, due to the fact that the thread monitor does not detect any more thread over a predetermined time period, the displacement of the flow element from the first position into the second position is initiated by the control system, in order to discard the cut thread.

In order to save energy, it is advantageous when the flow element is moved into a third position after the discharge of the thread, in order to block the air flow through the suction chamber. As a result, the suction chamber is blocked and the air flow is interrupted.

According to a refinement of the method, it is advantageous when the flow element is moved into the second position in order to seek the thread before the drawing-in, i.e., before the thread is sucked into the suction chamber. As a result, during the thread seeking, the air flow is not guided through the depositing surface, but rather is guided past the depositing surface through the first region. Since the depositing surface slightly blocks the air flow despite the air permeability, the volumetric flow rate through the suction chamber is also reduced during the passage through the depositing surface. If the air flow is now directed past the depositing surface with the aid of the flow element in order to seek the thread, the full volumetric flow rate is available for the thread seeking. As a result, an effectiveness of the drawing-in and intermediate storage is increased. In addition, it is also possible, as a result, to manage with only one level of negative pressure on the entire textile machine. By contrast, two different levels of negative pressure were frequently provided by two separate negative pressure ducts on conventional textile machines. For example, a first negative pressure duct was provided on a rotor spinning machine, which supplies the workstations with negative pressure for spinning, as well as a second negative pressure duct, which provides a higher level of negative pressure for service work at the workstations.

Preferably, in turn, the entry of the thread into the suction chamber is monitored by the thread monitor. As soon as the thread monitor detects the thread, a signal is output to the control system, which subsequently initiates the displacement of the flow element from the second position into the first position. The air flow is now directed through the depositing surface and through the second region, as described above, so that the thread can be stored for the interim. At the same time or after a predetermined time period after the first detection of the thread, the cutting of the thread is initiated, as described above, with the aid of the control system.

Further advantages of the invention are described in the following exemplary embodiments. Wherein:

FIG. 1a shows a schematic view of a workstation of a textile machine during regular operation, in which a thread is being wound onto a package, FIG. 1b shows a schematic view of the workstation in a situation in which the thread has broken and is traveling on the package,

FIG. 1c shows a schematic view of the workstation in a situation in which the thread is being sucked into the device for drawing in, intermediately storing, and discharging a thread,

FIG. 1d shows a schematic view of the workstation in a situation in which the thread has been returned into the workstation for piecing,

FIG. 2a shows a schematic sectional view of a device for drawing in, intermediately storing, and discharging a thread, comprising a flow element in a third position,

FIG. 2b shows a schematic sectional view of the device for drawing in, intermediately storing, and discharging a thread, comprising a flow element in a second position,

FIG. 2c shows a schematic sectional view of the device for drawing in, intermediately storing, and discharging a thread, comprising a flow element in a first position, including a thread, which is being deposited,

FIG. 2d shows a schematic sectional view of the device for drawing in, intermediately storing, and discharging a thread, comprising a flow element in the first position, including an intermediately stored thread,

FIG. 2e shows a schematic sectional view of the device for drawing in, intermediately storing, and discharging a thread, comprising a flow element in the second position, including a thread to be discharged,

FIG. 2f shows a schematic sectional view of the device for drawing in, intermediately storing, and discharging a thread, comprising a flow element in the third position,

FIG. 3 shows a schematic representation of the depositing of the thread on the depositing surface in the form of offset loops, and

FIG. 4 shows a schematic representation of the formation of a thread loop, including withdrawal of the intermediately stored thread out of the suction chamber.

FIG. 1 a shows a schematic sectional view of a workstation of a textile machine, on which the device 1 for drawing in, intermediately storing, and discharging a thread 2 can be advantageously utilized. The device 1 is represented merely symbolically in this case and is described in greater detail with reference to FIGS. 2a through 2f . The workstation is designed, in this case, as a thread-producing spinning station of a spinning machine comprising a spinning element 17. The workstation could also be designed as a spinning station of a winder, however.

In this case, in addition to the device 1, the workstation comprises a suction nozzle 20, which is connected to the device 1 and with the aid of which the thread 2 can be sucked in. The sucking-in of the thread 2 can be monitored with the aid of a thread monitor 13, which, as represented in this case, can be arranged in the exit region of the suction nozzle 20, in a suction tube or intermediate piece (not represented) adjoining the suction nozzle, or directly in the device 1, as is apparent, for example, from FIGS. 2a through 2f . The device 1 could also be designed as one piece with the suction nozzle 20 in this case. The suction nozzle 20 is arranged at a package 21. With the aid of the suction nozzle 20, a thread 2 traveling on the package 21 after an interruption of production can be sucked in. The package 21 is driven by a winding roller 22 in the direction of rotation 23 this case. The thread 2 is produced by the spinning element 17 and is drawn off by delivery rollers 18. In the present representation, the thread also extends through the suction nozzle 20 during production. The thread 2 enters the suction nozzle 20 through an opening 19 and exits the suction nozzle 20 at its mouth, in order to be wound onto the package 21. The device 1 can also be utilized, however, on a workstation, at which the thread extends outside the suction nozzle 20 during the production thereof and enters the suction nozzle 20 only for piecing or splicing.

In order to be able to convey the thread 2 to the spinning element 17 again in the event of a thread break, a holder 24 comprising an eyelet 26 is arranged adjacent to the spinning element 17. The holder 24 can be swiveled through the opening 19 into the suction nozzle 20, so that the eyelet 26 is located in the suction nozzle 20. Moreover, a sealing element 25 is arranged on the holder 24, which seals the opening 19 after the eyelet 26 has been swiveled therein.

FIG. 1b shows a schematic sectional view of the workstation, in which the thread 2 (not represented here) travels on the package 21 after an interruption of production, for example, due to a thread break. In order to be pieced again, the thread 2 must be sought on the package 21 and must be unwound to a certain length, wherein the seeking takes place with the aid of the suction nozzle 20 and the device 1.

For this purpose, the holder 24, including the sealing element 25, is swiveled upward into the opening 19. The eyelet 26 arranged on the holder 24 is introduced into the suction nozzle 20, so that, when the thread 2 is drawn into the suction nozzle 20, the thread 2 is also guided through the eyelet 26. The drawing-in of the thread 2 takes place with the aid of an air flow 4. In order to generate the air flow 4, the suction nozzle 20 is connected via the device 1 to a negative pressure source (not represented here), for example, to a negative pressure duct of the textile machine.

FIG. 1c shows the workstation in a further situation, in which the end 7 of the thread 2 as well as the thread 2 are drawn off the package 21 and are directed through the eyelet 26 into the device 1.

FIG. 1d shows the workstation in a further situation, comprising a thread 2, which has been guided back to the spinning element 17. A thread loop 29 was initially formed from the thread 2 guided through the eyelet 26 by way of the holder 24 having been swiveled downward. The formation of the thread loop 29 is described in greater detail with reference to FIG. 4. A cutting unit 27 is arranged in the region of the spinning element 17, which cuts the thread 2 or the thread loop presented to the cutting unit 27, in order to be pieced. As a result, two pieces result from the thread 2, namely the thread 2 cut off by the cutting unit 27, comprising a newly created end 7, which is discarded with the aid of the device 1, and a thread 2 to be pieced, which is guided to the spinning element 17 again.

While the above-described method steps are carried out, the air flow 4 must also be directed through the suction nozzle 20 and the device 1 in a different way. For this purpose, a depositing surface 5 and a flow element 6 are arranged in the device 1, the modes of operation of which are described in the following FIGS. 2a through 2f . It is to be noted with respect to FIGS. 2a through 2f that the device 1 and the air flow 4 are represented in a manner opposite to that with respect to the device 1 and the air flow 4 from FIGS. 1a through 1d . In FIGS. 1a through 1d , the air flow 4, starting from the opening 19, flows through the suction nozzle 20 and the device 1 from right to left in the drawing, whereas the air flow 4 from FIGS. 2a through 2f flows through the device 1 from left to right in the drawing.

FIGS. 2a through 2f each show a sectional representation of the device 1 during different method steps. The device 1 comprises a suction chamber 3 including an exit opening 9, at which negative pressure is applied in order to generate the air flow 4. For this purpose, the exit opening 9 is connected, for example, to a negative pressure duct of the textile machine. The thread 2 can be sucked into the device 1 and transported through the device 1 with the aid of the air flow 4. Moreover, a depositing surface 5 is arranged in the suction chamber 3, which is air-permeable and is impermeable to the thread 2 and on which the thread 2 can be intermediately stored. The depositing surface 5 can be designed, for example, as a screen or as a perforated piece of sheet metal. The depositing surface 5 can also be made of a plastic. Moreover, a flow element 6 is arranged in the suction chamber 3, with the aid of which the air flow 4 can be directed through the device. Moreover, the suction chamber 3 comprises an entry opening 8, through which the thread 2 can be sucked into the suction chamber 3 and directed to the depositing surface 5. The thread 2 can exit through the exit opening 9 and can then be discarded.

The depositing surface 5 subdivides the suction chamber 3 into a first region 14 and a second region 15. The first region 14 is utilized as a thread store, in which the thread 2 can be stored for the interim. In this case, the depositing surface 5 is arranged in parallel to the direction of flow and in a central region of the suction chamber 3. The depositing surface can also be arranged at an angle to the direction of flow, however.

The flow element 6 is arranged at the end 28 of the depositing surface 5 located at the rear in the direction of the air flow 4. The air flow 4 can be guided with the aid of the flow element 6, so that the air flow 4 can be directed through the depositing surface 5 or past the depositing surface 5. Moreover, the suction chamber 3 can be sealed off with the aid of the flow element 6, so that the air flow 4 is interrupted. In order to be able to guide the air flow 4 with the aid of the flow element 6, the flow element 6 can be rotated about a rotational axis 10 in this exemplary embodiment.

The suction chamber 3 comprises a first stop 11, against which the flow element 6 can be rotated. When the flow element 6 has contact with the first stop 11 (see FIGS. 2c and 2d ), the flow element 6 is located in a first position, in which the air flow 4 is guided through the depositing surface 5 into the second region 15 and through the second region 15. The air flow 4 through the first region is blocked in this case.

The suction chamber 3 also comprises a second stop 12, against which the flow element 6 can also be rotated. The flow element 6 is located in a second position, in which the air flow 4 is guided past the depositing surface 5. When the flow element 6 has been moved against the second stop 12, the flow element 6 blocks the second region 15. When the flow element 6 seals off the second region 15 at the second stop 12, the air flow 4 can no longer flow through the depositing surface 5 and, instead, is guided past the depositing surface 5 through the first region 14.

In deviation from the shown representation, the stops 11, 12 are not absolutely necessary. It would also be possible, for example, to set the correct position of the flow element with the aid of a stepper motor.

The suction chamber 3 can also be completely blocked off with the aid of the flow element 6. For this purpose, in this case, the flow element 6 can be displaced into a third position, so that the flow element 6 completely covers the exit opening 9 of the suction chamber 3 and consequently seals it. As a result, the air flow 4 is completely interrupted.

The device 1 according to the present example also comprises a thread monitor 13, with the aid of which the thread 2 can be detected in the suction chamber 3. The thread monitor 13 can be, for example, an optical sensor, such as a light barrier sensor, and/or a microwave sensor, which can preferably contactlessly detect whether a thread 2 is located in the suction chamber 3, or not. Alternatively or also in addition to the shown arrangement of the thread monitor 13, it would also be possible to arrange a thread monitor 13 directly in front of the entry opening 8 in the suction nozzle 20 (see FIGS. 1a through 1d ) or in front of an intermediate piece.

The sequence of the method for drawing in, intermediately storing, and discharging the thread 2 is now described with reference to the following FIGS. 2a through 2 f.

FIG. 2a shows the device 1 when, for example, the thread 2 is normally spun with the aid of the spinning element 17 and is wound onto a package 21 (cf. FIG. 1a ). There is no thread break or the like. The drawing-in and handling of the thread 2 is not required, and so, in order to save energy, the flow element 6 completely covers the exit opening 9 and, as a result, seals it, so that the air flow 4 is interrupted. The flow element 6 is located in the third position in this case.

FIG. 2b shows the device 1 when the thread 2 has been broken. In order to be able to piece the thread 2 again, a thread 2 traveling on the package 21 is sought with the aid of the air flow 4. For this purpose, the flow element 6 is displaced into the second position, wherein the flow element 6 is moved against the second stop 12, so that the flow element 6 blocks the second region 15 with the aid of the stop 12, in order to prevent the air flow 4 from flowing through the depositing surface 5. As a result, the air flow 4 is guided into the suction chamber 3 through the entry opening 8, past the depositing surface 5, through the first region 14, and out of the suction chamber 3 through the exit opening 9. An advantage thereof is that the air flow 4 is not decelerated by the depositing surface 5, and so a high suction effect is available for seeking the thread 2 on the package 21. The thread 2 is therefore sought on the package 21 with the aid of the air flow 4 having a maximum volumetric flow rate. Alternatively, it would also be possible, however, to guide the air flow 4 through the depositing surface 5 while seeking the thread. The advantage in this case would be a lesser control effort, since the flow element 6 needs to be displaced less often.

A thread monitor 13 is arranged in the region of the entry opening 8, which can detect the presence of a thread 2 in the region of the entry opening 8. Whether the thread seeking was successful can therefore be detected at a very early point in time. The thread monitor 13 is connected to a control system (not shown here), which can displace the flow element 6 upon detection of the thread 2 in this exemplary embodiment. After the end 7 of the thread 2 has entered, which is detected with the aid of the thread monitor 13, the control system can prompt the flow element 6 to be displaced into the first position, so that the air flow 4 is guided through the depositing surface 5. In the present exemplary embodiment, this takes place in that the flow element 6 is rotated against the first stop 11. Since the thread monitor 13 is arranged ahead of the flow element with respect to the direction of the air flow 4, the flow element 6 can be advantageously displaced even before the thread 2 has reached the first stop 11. As a result, the thread 2 can be reliably deposited onto the depositing surface 5, wherein a pinching of the thread 2 between the first stop 11 and the flow element 6 is prevented. In the alternative embodiment, in which the seeking of the thread 2 takes place with the aid of an air flow 4 guided through the depositing surface 5, this step of displacing the flow element 5 is omitted, since the flow element 5 is already located in the first position.

FIG. 2c shows the device 1 after the detection of the thread 2 with the aid of the thread monitor 13. The flow element 6 has been displaced into the first position, wherein, in this exemplary embodiment, the flow element 6 has been moved against the first stop 11, in order to guide the air flow 4 through the air-permeable depositing surface 5. Since the depositing surface 5 is impermeable to the thread 2, however, a thread ball 16 forms in the thread storage chamber 7, wherein the thread 2 is intermediately stored or deposited on the depositing surface 5.

The formation of the thread ball 16 is advantageous, since the thread ball 16 is compressed and takes up less space in a collection container as compared to the outstretched thread 2. In addition, with respect to the outstretched thread 2, there is the risk that the thread 2 will get tangled on components in the suction chamber 3 or on components of a negative pressure duct, into which the thread 2 is discharged, and, consequently, must be manually removed, which is time-consuming. In this case, the thread ball 16 is represented as a disorderly depositing of the thread 2. Preferably, however, the depositing of the thread 2 takes place in an orderly manner, in order to be able to remove the thread 2 from the suction chamber 3 again. This is represented in FIG. 3.

FIG. 2d shows the device 1 including the thread ball 16 intermediately stored in the first region 14, after the thread 2 has been cut by the cutting unit 27 (cf. FIG. 1d ). The successful cutting of the thread 2 can also be detected with the aid of the thread monitor 13. This can take place in that the thread monitor 13 detects no thread 2 at all over a predetermined time period.

FIG. 2e shows the device 1 including the thread ball 16, which is being discarded. For this purpose, the flow element 6 has been displaced into the second position, so that the second region 15 is sealed off and the air flow 4 is guided past the depositing surface 5. The displacement of the flow element 5 is initiated by the control system as soon as the thread monitor 13 has detected the successful cutting of the thread 2. The air flow 4 can flow, essentially unhindered, through the first region 14 of the suction chamber 3 and, as a result, carries the thread ball 16 away through the exit opening 9. It is particularly advantageous in this case that the displacement of the flow element 5 into the second position takes place in the same direction in which the thread ball 16 is discharged. As a result, it can be ensured that the thread 2 does not become stuck on the flow element 5.

FIG. 2f shows the device 1 after the thread ball 16 has been discarded. In order to save energy, the flow element 6 has been displaced into the third position again, so that the flow element 6 seals off the exit opening 9. The thread 2 is pieced and the regular operation is started again at the workstation.

FIG. 3 shows, in a schematic representation, a loop-shaped and laterally offset depositing of the thread 2 on the depositing surface 5 in the suction chamber 3. Due to the depositing surface 5 being arranged obliquely or in parallel to the direction of flow, the drawn-in end 7 of the thread 2 is initially sucked to a first portion of the depositing surface 5, for example, the left edge region in this case, due to the still very high air flow, where the end 7 is deposited along with a first section of the thread 2. At the same time, the depositing surface 5 becomes obstructed to a small extent. Due to the turning of the thread 2, the thread 2 then forms a loop and a second section of the thread 2 is deposited on the depositing surface 5 in parallel to the first section, since the thread 2 is preferably deposited at the point where there is no thread 2 yet and the air flow 4 through the suction chamber 3 is still active. In this way, while additional thread 2 is constantly delivered from the package 21 (symbolized here with the aid of an arrow), the entire depositing surface 5 is gradually filled, in a loop-shaped manner, with sections of the thread 2 lying essentially in parallel to one another. Twists and entanglements of the thread 2 can be largely avoided as a result, so that the thread 2 can be easily withdrawn from the suction chamber again.

The withdrawal of the intermediately stored thread 2 from the suction chamber 3 is required, for example, in order to form a thread loop 29 during piecing, which is described in the following with reference to FIG. 4.

FIG. 4 shows a schematic sectional view of a workstation of a textile machine, as in the case of FIGS. 1a through 1d . Identical components are provided with the same reference numbers as in FIGS. 1a through 1d , and so only the differences from the aforementioned figures will be described in the following. A situation is represented, in which a thread loop 29 has been formed from the thread 2 by the holder 24 having been swiveled downward after the thread 2 has been sucked into the device 1.

In order to form the thread loop 29, it is necessary to provide an additional length of the thread (symbolized in this case with the aid of the dotted line). This can take place, according to the present example, in that a defined length of the thread, which corresponds to this necessary additional length, has been previously sucked in. As described above, the defined length can be sucked in, in that the package 21 is rotated in reverse for a certain time period or for a certain number of revolutions. Since the flow element 6 is located in the first position during the sucking-in, a constant, uniform retention force is exerted onto the thread 2, which holds the thread 2 under a uniform tension and, as a result, prevents a lap formation in the sucked-in thread 2. In addition, the thread is deposited, in an orderly manner, in offset loops in the suction chamber 3 of the device 1.

In order to form the thread loop 29, the drive of the package 21, specifically the winding roller 22 in this case, is stopped and the holder 24 is swiveled downward. The flow element 6 remains in the first position. The thread loop is formed, with the intermediately stored thread ball 16 being opened, in the suction chamber 3 with the package 21 stopped. Since a retention force is still exerted upon the thread 2 by the air flow 4 during the downward swiveling, a constant retention force is also exerted upon the thread 2 during the formation of the thread loop 29, which prevents a lap formation.

Alternatively to the formation of the thread loop from the intermediately stored thread, which is described in connection with FIG. 4, it is also possible, of course, to form the thread loop in a known way while the thread is unwound from the package. In this case, the entire thread intermediately stored in the device is discharged after the cutting, in that the flow element is moved into the second position and, as a result, the intermediately stored thread is sucked out and discarded with the aid of the air flow.

The present invention is not limited to the represented and described exemplary embodiments. Modifications within the scope of the claims are also possible, as is any combination of the features, even if they are represented and described in different exemplary embodiments.

LIST OF REFERENCE NUMBERS

1 device for drawing in, intermediately storing, and discharging the

thread

2 thread

3 suction chamber

4 air flow

5 depositing surface

6 flow element

7 end of the thread

8 entry opening

9 exit opening

10 rotational axis

11 first stop

12 second stop

13 thread monitor

14 first region

15 second region

16 thread ball

17 spinning element

18 delivery roller

19 opening

20 suction nozzle

21 package

22 winding roller

23 direction of rotation

24 holder

25 sealing element

26 eyelet

27 cutting unit

28 rear end

29 thread loop 

1. A device (1) for drawing in and intermediately storing a thread (2), comprising a suction chamber (3), in particular for withdrawing a thread (2) from a package (21), wherein the suction chamber (3) includes an entry opening (8) and an exit opening (9), which define a direction of flow of the device (1), and wherein a negative pressure can be applied to the exit opening (9) in order to generate an air flow (4) through the suction chamber (3), comprising a depositing surface (5), which is arranged in the suction chamber (3), is air-permeable, and is impermeable to the thread (2), on which the thread (2) can be intermediately stored, and comprising a flow element (6) arranged in the suction chamber (3), characterized in that the suction chamber (3) is divided into a first region (14) and a second region (15) with the aid of the depositing surface (5) and that the flow element (6) is displaceable between a first position, in which the air flow (4) is guided through the depositing surface (5) and through the second region (15), and a second position, in which the air flow (4) is guided past the depositing surface (5) through the first region (14). 2-21. (canceled) 